Sunday, May 5, 2013

I'm now on sabbatical, next due in the office in August 2014. Been thinking this would be a good excuse/motivation to resurrect the blog (quiet for the last 5 years), but hadn't yet found something I felt like writing about.

So much for leaving the classroom: my inaugural sabbatical post is about class sizes.

The NYTimes has an op-ed on whether class size counts. The article is about pre-college, not college classes. Roughly, the piece discusses a proposal under which high performing teachers get additional pay in exchange for taking on larger classes. The piece doesn't discuss how much larger, but does cite a national survey that asked teachers about taking on 3 additional students in exchange for $10K. Interestingly, only 42% of teachers wanted this deal, while 47% would turn down the raise in exchange for 3 fewer students. The piece also discusses the lack of actual research on the effect of class sizes, noting that the effect may be quite different for different kinds of students.

This struck me in part because my department is potentially facing an increase in students interested in taking Computer Science next year. For the past three years, I've taught the second course in our CS sequence (OO program design and data structures), last year topping out at 235 students across two lecture sessions and 9 lab sections. And honestly, trying to find ways to give the support associated with smaller classes to that many students burned me out enough that I'm only now really figuring out what I want to do with my sabbatical.

But it has left me thinking a lot about what we associate with "small classes", what parts of that actually matter, and how we can provide it as class sizes outstrip resources.

Access to help is perhaps the biggest issue. In practice, though, help needs are not directly proportional to class sizes. How many times have I taught smaller (40ish) person classes and not had a single student come to office hours or request appointments? Out of my 235 students, I'd estimate that there were roughly 25-30 students who actually came to my office or asked for help with any regularity (I know many more used the teaching assistants). The point is that a class of 200+ students who don't need help is a very different beast than a class of students who do need help. The op-ed raises this distinction, but at the college level, we seem to make our allocations more on simple student/staff ratios.

Quality feedback on student work follows close behind. Good teaching involves showing students who don't think they need help that they still have things to learn. Unless someone is actually reading student work, we miss those opportunities for deep education. I still insist on having my staff actually read all the code that gets submitted (rather than just auto-grading against test suites), but we're losing the scale battle there.

Avoiding anonymity is another issue I worry about: even if a student never expects to seek help, large classes feel impersonal. At a time when students are trying to work out who they are and what they care about, this is problematic. Not problematic enough, however, to justify additional resources.

I will be spending at least part of my sabbatical better understanding how cognitive tutors and other computer-based learning aids could help with these problems. I don't want to fully automate my class. Being honest with myself, I'm looking for ways to mitigate the guilt of not being able to support each and every student in line with my values as a teacher. Having that support come entirely from a human teacher isn't feasible, nor do I suspect necessary, or even optimal. There are interesting blended human-computer instructional systems waiting to be built for teaching in large classes (lots of progress exists on the systems side, but the teacher/tool interaction seems less developed). If I can come off sabbatical more comfortable with the level of support I can provide, and rested enough to hold up my end of the bargain, I'd call it a success.